Thursday, 18 December 2014

'Low-GI' Diet May Not Benefit Blood Sugar

Focus should be on eating healthy foods rather than glycemic index, experts say

WebMD News from HealthDay

By Amy Norton

HealthDay Reporter

WEDNESDAY, Dec. 17, 2014 (HealthDay News) -- Diets low in "glycemic index" are touted as a way to help prevent diabetes and heart disease. But a new study suggests that as long as people are eating healthily, they don't need to obsess over glycemic index.

In fact, researchers found that overweight adults placed on a low-GI diet actually showed less sensitivity to insulin than those on a high-GI diet. Insulin is the body's key blood-sugar-regulating hormone, and a decline in insulin sensitivity can eventually lead to type 2 diabetes.

The findings, reported online on Dec. 16 in the Journal of the American Medical Association, were unexpected, experts said. But they also called the results "good news."

"Low-GI diets are difficult to follow," said Dr. Frank Sacks, the lead researcher on the study and a professor of cardiovascular disease prevention at the Harvard School of Public Health.

"If you don't have to worry about foods' glycemic index, that makes it easier to follow a healthy diet," Sacks said.

Glycemic index is a measure of how an individual food affects blood sugar levels. Simply put, a food with a high GI -- like white bread or potatoes -- causes a surge in blood sugar; a food with a low GI -- many vegetables, for example -- produces a more gradual change in blood sugar.

In theory, a diet lower in GI could help control body weight or lower the risk of type 2 diabetes, a condition that causes high blood sugar levels.

But, Sacks pointed out, calculating GI is no easy task. An individual food's GI changes depending on several factors, including its processing or how it's cooked. As an example, Sacks noted that al dente pasta has a lower GI than soft-cooked pasta.

Plus, the general notion that eating high-GI foods causes diabetes is "overly simplistic," said Dr. Robert Eckel, a professor of medicine at the University of Colorado in Aurora.

And based on the new findings, "GI is not worth worrying about," said Eckel, who wrote an editorial published with the findings.